Health conditions, such as thyroid problems, allergies or immune disorders.

Irritation caused by use of contact lenses, or after LASIK surgery.

Pregnancy, hormone replacement therapy or some homeopathic remedies.

Not blinking frequently enough during use of a computer screen.

-- Diana Kohnle

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.